Electron discharge tube having an anode forming part of a lecher-line with a heat dissipating element

ABSTRACT

A high-power electron discharge tube having an anode forming part of a Lecher line and being cooled by heat dissipation. Means to dissipate the heat generated by the anode are located at a voltage node or at a current antinode, i.e., a point at which, for a given frequency, the voltage is a minimum and current a maximum.

United States Patent lnventor App]. No. Filed Patented Assignee PriorityOtto G. Voss Ahrensburg Scheunenkoppel, Germany Dec. 9, 1968 Jan. 26,1971 U. S. Philips Corporation New York, NY.

a corporation of Delaware Dec. 13, 1967 Germany ELECTRON DISCHARGE TUBEHAVING AN ANODE FORMING PART OF A LECHER-LINE WITH A HEAT DISSIPATINGELEMENT 4 Claims, 2 Drawing Figs.

U.S. C1 315/39, 33/82; 331/91 313/42, 313/46 Int. Cl I-IOlj 7/46,

HOlj 19/80 [50] Field of Search 333/82A.

82BT, 83T; 313/4246; 315/39; 331/99, 100

[56] References Cited UNITED STATES PATENTS 2,151,912 3/1939 Habann eta1 333/82AX 2,265,833 12/1941 Fritz 333/82A 2,285,662 6/1942 Hutcheson313 4 2,505,251 4/1950 Knol et a1. 333/82AX 2,735,941 2/1956 Peck333/82AX Primary Examiner1-lerman Karl Saalbach AssistantExaminer-Saxfield Chatmon, Jr. Att0rneyFrank R. Trifari ABSTRACT: Ahigh-power electron discharge tube having an anode forming part of aLecher line and being cooled by heat dissipation. Means to dissipate theheat generated by the anode are located at a voltage node or at acurrent antinode, i.e., a point at which, for a given frequency, thevoltage is a minimum and current a maximum.

PATENTEU JAN 26 I97! INVENTOR.

OT TO 6. VOSS AGEN ELECTRON DISCHARGE TUBE HAVING AN ANODE FORMING PARTOF A LECI-IER-LINE WITH A HEAT DISSIPATING ELEMENT The invention relatesto a high-power discharge tube suitable for wavelengths in which theelements determining the frequency are distributed along the conductors,the tube comprising a device which cools the anode by heat dissipation.

The cooling of the anode of tubes for high power and high frequencieshas always experienced great difficulties, since the anode conveys notonly a high direct voltage, but also highfrequency voltages. Therequirements imposed upon a good thermal contact of the anode with thecooling medium and upon a good insulation therefore were contradictory.

In German Patent Specification No. 837,577, for example, an electrontube is described in which heat of the anode is conducted through asupply conductor in the form of a pin to a cooling device outside thetube. The coefficients of expansion of the materials were chosen to besuch that the contacting surfaces of the pin and the cooling componentswere forced more strongly against each other upon heating so that thetransfer of heat improved at higher temperatures. However, such aconstruction is not suitable for very high frequencies, because theydisturb resonance circuits.

It is furthermore known from Us. Pat Specification No. 3,054,012 toconstruct a tube entirely from ceramic components, the anode consistingof a metal law layer which is formed on a ceramic part of the wall. Theceramic parts have a large wall thickness so that they readily dissipatethe heat to a cooling member.

However, such large ceramic bodies cause considerable dielectric losseswhen they are arranged in the vicinity of components which convey largehigh-frequency voltages. Therefore, this embodiment is not suitableeither for discharge tubes, in which the elements which determine thefrequency are distributed along the conductors for example, in tubes inwhich the anode forms part of a Lecher system.

The said drawbacks can be avoided in an electron tube for high power andfor a frequency range in which the elements which constitute theoscillatory circuit are distributed along the line(s), the tubecomprising an anode which is cooled by heat dissipation, if, accordingto the invention, the anode which forms part of a Lecher system iscooled by dissipating the heat at a location of the Lecher system, wherethe high frequency voltage shows a minimum.

At this location the high frequency current will generally show amaximum.

The anode itself may be constituted as a Lecher system. In

order to reduce the dimensions of the Lecher system a tuning capacitormay be providedv The invention will be described with reference to theaccompanying drawing, in which:

FIG. I is a longitudinal sectional view of a tube having an anode whichconstitutes a Lecher system; and

FIG. 2 shows a similar sectional view rotated through with respect toFIG. I.

Referring now to the FIGS., reference numeral I denotes a ceramic wallof the tube which is sealed by a bottom plate 2. in the vacuum space 3there is a cathode 4, a control grid 5 and the anode which consists oftwo strip-shaped parts 7 and 8 which constitute a Lecher system outsidethe envelope I and which system is terminated by a conductor 11. Inorder to reduce the dimensions of the Lecher system, a tuning capacitor15 is provided which can be tuned by means of the shaft 14. The strips 7and 8 are passed through the envelope 1 in a vacuumtight manner at 9 and10. The terminal conductor 11 is located in a region where thehigh-frequency voltage shows a minimum and is in a good heat-conductingconnection with an insulating member 12 which is connected to a coolingmember 13. This cooling member 13 comprises cooling tins 16. The shorterthe Lecher system, the lower the thermal resistance of the active anodeparts to the terminal conductor 11, and hence the better the heatdissipation to the cooling member 13 and the lower the anodetemperature. As shown in FIGS., the conductors 7 and 8 are strip-shaped.Since the cooling member is not located near a part with a largehighfrequency alternating voltage, it causes no extra losses.

I claim:

1. A high-power electron discharge tube for a frequency range in whichthe elements which constitute an oscillatory circuit are distributedalong a line, the tube comprising an anode which is cooled by heatdissipation and which forms part of a Lecher system having twoconductors that are shorted at the terminal opposite to the terminalintegral with said tube anode, and means to dissipate the heat mountedon and in thermal contact with said shorted terminals at the saidshorted location of the Lecher system where the high-frequency voltageshown a minimum.

2. An electron tube as claimed in claim 2, wherein the heat dissipatingmeans is at a location where the high-frequency current is maximum.

3. An electron tube as claimed in claim 1 wherein the anode isconstituted as a Lecher line.

4. An electron tube as claimed in claim 3, wherein the dimensions of theLecher system are kept comparatively short by the addition of a tuningcapacitor.

73 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,558,969 Dated Januar 26, Q71

lnven y OTTO G voss It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 1, line 5, after "high-power" insert -electron Signed and sealedthis 11th day of May 1971 (SEAL) Attest:

EDWARD M. FLETCHER,JR. WILLIAM E SCHUYLER t Attesting OfficerCommissioner of Patenw

1. A high-power electron discharge tube for a frequency range in whichthe elements which constitute an oscillatory circuit are distributedalong a line, the tube comprising an anode which is cooled by heatdissipation and which forms part of a Lecher system having twoconductors that are shorted at the terminal opposite to the terminalintegral with said tube anode, and means to dissipate the heat mountedon and in thermal contact with said shorted terminals at the saidshorted location of the Lecher system where the high-frequency voltageshown a minimum.
 2. An electron tube as claimed in claim 2, wherein theheat dissipating means is at a location where the high-frequency currentis maximum.
 3. An electron tube as claimed in claim 1 wherein the anodeis constituted as a Lecher line.
 4. An electron tube as claimed in claim3, wherein the dimensions of the Lecher system are kept comparativelyshort by the addition of a tuning capacitor.